The present invention relates generally to interface devices for allowing humans to interface with computer systems, and more particularly to computer interface devices that provide input from the user to computer systems and implement force feedback to the user.
Using an interface device, a user can interact with an environment displayed by a computer system to perform functions and tasks on the computer, such as playing a game, experiencing a simulation or virtual reality environment, using a computer aided design system, operating a graphical user interface (GUI), or otherwise influencing events or images depicted on the screen. Common human-computer interface devices used for such interaction include a joystick, mouse, trackball, stylus, tablet, pressure-sensitive ball, or the like, that is connected to the computer system controlling the displayed environment. Typically, the computer updates the environment in response to the user's manipulation of a user-manipulatable physical object such as a joystick handle or mouse, and provides visual and audio feedback to the user utilizing the display screen and audio speakers. The computer senses the user's manipulation of the user object through sensors provided on the interface device that send locative signals to the computer.
In some interface devices, haptic feedback is also provided to the user, also known as “force feedback.” These types of interface devices can provide physical sensations which are felt by the user manipulating a user manipulable object of the interface device. For example, the Wingman Force joystick or the Wingman Force Feedback Mouse from Logitech Inc. may be connected to a computer and provides forces to a user of the controller. One or more motors or other actuators are used in the device and are connected to the controlling computer system. The computer system controls forces on the joystick in conjunction and coordinated with displayed events and interactions by sending control signals or commands to the actuators. The computer system can thus convey physical force sensations to the user in conjunction with other supplied feedback as the user is grasping or contacting the joystick or other object of the interface device. For example, when the user moves the manipulatable object and causes a displayed cursor to interact with a different displayed graphical object, the computer can issue a command that causes the actuator to output a force on the user object, conveying a feel sensation to the user.
Force feedback can be used to communicate ideas and messages as well as effects. Forces can in many instances provide additional information to a recipient of the message that may not be apparent in a text or voice message. For example, a text message sent to another user over the Internet may not include information indicating how strong the user feels about the topic expressed or other message subtext. Users can try to express this subtext using well-known icons or symbols known as “emoticons,” which are iconic representations of emotions or messages, such as the “smiley” to indicate a humorous message, expressed as a colon and right parenthesis mark, :), which resembles a face smiling when viewed from the side. Variations of the smiley emoticon can express a variety of other emotions. However, such emoticons and symbols are limited in the complexity of the messages they convey and the range of different messages possible. Haptic feedback, in contrast, can offer much more complex and direct ways to express such subtext to other users in a more compelling fashion.